JP5238932B2 - Aortic valve stent graft - Google Patents

Description

The present invention relates to an endoluminal prosthesis such as an aortic valve stent graft.
The described embodiments relate to implantable medical devices and methods, and more particularly to implantable medical devices for repair of a valve in a damaged lumen, such as an aortic valve, and the medical device And how to embed.

The aortic valve functions as a one-way valve between the heart and other parts of the body. Blood is pumped from the left ventricle of the heart through the aortic valve to the aorta, thus supplying blood to the body. During heart contraction, the aortic valve is closed, preventing blood from flowing back into the heart.

  Aortic valve damage is caused by congenital defects, natural aging, infections or scarring. Over time, calcium may accumulate around the aortic valve, causing the valve to not open and close properly. Certain types of damage can cause the valve to “leak” and cause “aortic regurgitation” or “aortic regurgitation”. Aortic regurgitation can cause an extra workload on the heart, ultimately weakening the myocardium and resulting in heart failure.

  After the aortic valve is severely damaged, the valve needs to be replaced to prevent heart failure and death. One current method involves using a balloon expandable stent to place a prosthetic valve at the location of the missing aortic valve. Other current methods relate to using a self-expanding stent to place a prosthetic valve at the aortic valve location. However, these techniques are incomplete. A normal aortic valve is suspended from above via a fitting to the wall of the tubular venous sinus between the coronary ostium and has a full sized and shaped leaflet to fill the space in the annulus. It works well to have. It is difficult to replicate these functions in a valve that is a percutaneous implant. The size of the implant location depends on the unpredictable outcome of the heavily calcified original valve and its balloon annulus balloon expansion. Balloon dilation can result in degradation of valve function with a continuous gradient or back flow through the valve. The diameter of the aortic valve is small, so the diameter of the expansion is not always predictable, especially when using self-expanding stents. In addition, the shape of the aortic valve is not circular, which can also lead to back flow outside the valve.

SUMMARY OF THE INVENTION The present invention seeks to provide an improved endoluminal prosthesis, an improved aortic valve, and an improved replacement method for an aortic valve in a patient.

According to one aspect of the present invention, an endoluminal prosthesis as specified in claim 1 is provided .

  The described embodiments provide an endoluminal prosthesis for aortic valve replacement in a subject. In one embodiment, the prosthesis comprises a first stent, a tubular conduit, and a second stent. The tubular conduit may comprise a valve, and at least a portion of the tubular conduit overlaps at least a portion of the first stent. The second stent overlaps at least a portion of the tubular conduit. In use, the first stent, the tubular conduit, and the second stent are coaxially arranged to pass fluid in one direction through the prosthesis.

In one embodiment, the first stent comprises a balloon expandable stent and the second stent comprises a self-expanding stent. The self-expanding stent may at least partially surround the tubular conduit, and the tubular conduit may at least partially surround the balloon expandable stent. Alternatively, both the balloon expandable stent and the self-expanding stent may at least partially surround the tubular conduit. The valve may comprise a prosthetic valve, and the prosthetic valve may be located at the distal end of the tubular conduit.
In some embodiments, at least one of the first stent and the second stent includes a braided bottle stent.

  In one exemplary surgical method, an endoluminal prosthesis may be introduced into the vasculature. The endoluminal prosthesis includes a first stent, a tubular conduit with a valve, and a second stent. At least a portion of the tubular conduit overlaps at least a portion of the first stent. At least a portion of the tubular conduit overlaps at least a portion of the second stent. The prosthesis is advanced toward the aortic annulus within the vasculature. Thereafter, at least a portion of the prosthesis is expanded to engage the aortic annulus.

  The first stent, the tubular conduit, and the second stent may be advanced into the vasculature sequentially or simultaneously. The first stent, the tubular conduit, and the second stent are configured to pass fluid in one direction through the prosthesis and substantially or completely inhibit backflow through the prosthesis during operation. Also good.

  Other systems, methods, features and advantages in accordance with the teachings herein will or will be apparent to those of ordinary skill in the art upon review of the following drawings and detailed description. Let's go. Such additional systems, methods, features, and advantages are intended to be within the scope of the claims.

  Embodiments of the invention will now be described, by way of example only, with reference to the accompanying drawings.

FIG. 3 is a partial cross-sectional view of the heart and aorta. It is a sectional side view of an endoluminal prosthesis. FIG. 3 is a top view of the prosthesis of FIG. 2. It is a bottom view of the prosthesis of FIG. It is a fragmentary sectional view of the aorta in which the prosthesis is embedded. It is another fragmentary sectional view of the aorta in which the prosthesis was embedded. FIG. 6 illustrates a braided stent. FIG. 6 is a plan view of one embodiment of a barb attached to a stent. FIG. 9 is a perspective view of a barb attached to the stent of FIG. 8. It is a side view of one embodiment of a barb. FIG. 10 is a side view of a portion of a stent having a spine loop facing outwardly from each apex. It is a figure of one Embodiment of the expansion period of the artificial valve. It is a figure of one Embodiment of the systole of an artificial valve. It is a side view of one Embodiment of the support frame for artificial valves. It is a top view of one embodiment of a support frame for an artificial valve. It is a figure which illustrates one Example of the artificial valve which has a support frame. It is a figure which illustrates the other Example of the artificial valve which has a support frame. FIG. 10 is a perspective view of selected portions of an indwelling device having a partially deployed aortic stent graft.

DETAILED DESCRIPTION In this application, the term “proximal” refers to the direction generally closest to the heart during a medical procedure. On the other hand, the term “distal” refers to the direction furthest away from the heart during a medical procedure.

  FIG. 1 shows a partial cross-sectional view of the heart 102 and the aorta 104. The heart 102 includes an aortic valve 106 that is not properly sealed. This defect in the aortic valve 106 causes blood to flow back from the aorta 104 to the left ventricle 108, resulting in a disease known as aortic valve regurgitation. The bicuspid mitral valve 100 generally prevents blood from flowing further back into the left atrium. Also shown in FIG. 1 are brachiocephalic artery 112, left common carotid artery 114, left subclavian artery 116, and right ventricle 120. A portion of the aorta 104, referred to herein as the ascending aorta 118, is shown disposed between the aortic valve 106 and the brachiocephalic artery 112.

  FIG. 2 shows a first embodiment of a prosthetic device in the form of an aortic stent graft 202. In this embodiment, the aortic stent graft 202 comprises three generally tubular members arranged in a coaxial configuration comprising a balloon expandable stent 204, a conduit 206 and a self-expanding stent 208 in order from the inside to the outside. Conduit 206 includes a prosthetic valve 210. The prosthetic valve 210 is shown in an open shape and allows blood flow in one direction through the prosthesis in the direction indicated by arrow 240. In the present embodiment, the conduit 206 is shown as a thin-walled conduit. Also in this embodiment, the prosthetic valve 210 is shown near the distal end of the conduit 206.

  The shape, size and dimensions of each member of the prosthetic device 202 may vary. As a result, the overall size and shape of the aortic stent graft prosthesis may vary. The size of the preferred prosthetic device is determined primarily by the diameter of the lumen (preferably a healthy valve / lumen combination) at the intended implantation location, and also by the desired length of the stent and the overall valve device. It is determined. Therefore, various aspects related to the structure of the prosthesis are determined by an initial assessment of the position of the patient's original aortic valve. For example, the position of the patient's native aortic valve determines the dimensions of the stent and tubular conduit, the type of valve material selected, and the size of the indwelling means. The length of the self-expanding stent 208 is sufficiently long to overlap the conduit 206 and extend to engage the ascending aorta 118.

  In the embodiment shown in FIG. 2, the conduit 206 is shown fully covering the length of the balloon expandable stent 204. However, in other embodiments, the conduit 206 may only partially cover the length of the balloon expandable stent 204. What is needed is that the length of the conduit 206 be sufficient to overlap at least a portion of the balloon expandable stent 204, thereby providing a bond that provides fluid flow through the prosthesis. Similarly, the length of the self-expanding stent 208 may vary. What is needed is that the length of the self-expanding stent 208 be sufficient to overlap the conduit 206, thereby providing a bond that provides fluid flow through the prosthesis.

  In the present embodiment, the tubular member is preferably uniform in the axial direction. Furthermore, the tubular member shown in FIG. 2 is shown in a generally cylindrical shape. In other embodiments, one or more of these tubular members may be formed with a curve. For example, one or more of these members may taper gradually. That is, these members may have a tubular shape that gradually narrows toward the distal side, or a tubular shape that gradually widens toward the distal side. The tubular member may further be elliptical, conical, or have a regular shape or a combination of irregular shapes that match the shape of the tissue of the transplant patient.

  FIG. 3 is a top view of the prosthesis of FIG. 2, showing the prosthetic valve 210 in the closed position. In this view, the prosthetic valve 210 is seen to be attached to the conduit 206. The artificial valve 210 shown in the present embodiment includes three leaflets. FIG. 3 also shows a self-expanding stent 208. As shown in FIG. 3, the plurality of tubular members are coaxial and are shown in a generally cylindrical shape. As noted above, in other embodiments, one or more of these tubular members may be curved, tapered, conical, or non-conforming to the shape of the lumen. It may have a regular shape.

  4 is a bottom view of the prosthesis of FIG. 2, showing the prosthetic valve 210 in the closed position. In this view, in addition to the conduit 206 and the self-expanding stent 208, the innermost member, the balloon expandable stent 204, is shown.

  The prosthesis of these embodiments may be introduced and placed in the subject's vasculature to reach the aortic annulus, as shown in FIGS. Preferably, the prosthesis has a compressed state for delivery and an expanded state when placed within an artery. When the prosthesis is placed and implanted at the aortic annulus, the prosthetic prosthetic valve functionally replaces the subject's aortic valve. Note the different embodiments of the implanted prosthesis shown in FIGS. In FIG. 5, the self-expanding stent 208 at least partially surrounds the tubular conduit 206 and the tubular conduit 206 at least partially surrounds the balloon expandable stent 204. In FIG. 6, both the balloon expandable stent 204 and the self-expanding stent 208 at least partially surround the tubular conduit 206. In both embodiments, the prosthesis allows unidirectional flow of fluid from the heart to the aorta.

  The members constituting the prosthesis may be introduced and placed at the same time. In this situation, each element may be attached to a balloon catheter. The balloon is arranged in the aortic annulus and then expanded to expand the aortic annulus substantially simultaneously and deploy the balloon expandable stent 204 and the rest of the prosthesis. By deploying the elements of the prosthesis at substantially the same time as the annulus is expanded, the potentially fatal backflow problem can be avoided.

  In other embodiments, individual members may be introduced and placed in sequence. If each element is placed in turn, because of the potentially fatal aortic regurgitation problem associated with dilating the aortic annulus and then inserting the prosthetic elements individually, You may need to stop blood flow.

  In other embodiments, simultaneous and sequential placement may be combined. That is, several members of the prosthesis may be placed simultaneously, while the other member or members may be placed in turn.

  The self-expanding stent 208 included in the prosthesis may be a modified Gianturco “Z stent” or any other type of self-expanding stent. The Z-stent structure is preferred for the linear portion of the aorta because it provides both large radial forces and longitudinal support.

  In certain preferred embodiments, the self-expanding stent 208 may be a braided stent, as shown in FIGS. As shown in FIGS. 6 and 7, a long open mesh stent is required even without the struts that would be required if the valve was supported only through an annular fitting. Provide downstream support. This stent structure requires flexibility, resistance to compressive forces, and a junction with the aorta that does not damage the tissue. Self-expanding stents have two sections: a lower (proximal) section with a small diameter and a constant length (for resistance to compression) and a larger diameter and a variable length (for flexibility). And an upper (distal) area. A braided stent such as a Wallstent may be provided with two such areas by changing the braid angle. If the stent is made of Nitinol, the exact braid shape may be determined by thermosetting after all the metal wires are bent and joined to the basic shape. The proximal end of the stent may be formed so as not to damage more tissue by connecting the ends of the metal wire as a ring.

  Typically, the prosthesis has a circular cross-section when fully expanded to conform to the generally circular cross-section of the vascular lumen. In one embodiment, the balloon expandable stent 204 and the self-expanding stent 208 are struts and sharp bends, or cusps that are arranged in a zigzag shape with the struts placed at an angle to each other and coupled to the sharp bends. , And may be included. The stent may include a curved or annular portion. This embodiment may be used with a wide variety of stents. These stents include, but are not limited to, shape memory alloy stents, expandable stents, and in situ formed stents. Any stent shape suitable for expansion to fit into the relevant tissue space may be used.

  Preferably, the self-expanding stent 208 is formed from Nitinol, stainless steel, or Elgiloy. Examples of other materials that may be used to form the stent are carbon or carbon fiber, tantalum, titanium, gold, platinum, inconel, iridium, silver, tungsten, cobalt, chromium, cellulose acetate, cellulose nitrate, silicone Polyethylene terephthalate, polyurethane, polyamide, polyester, polyorthoester, polyanhydride, polyethersulfone, polycarbonate, polypropylene, high molecular weight polyethylene, polytetrafluoroethylene, or other biocompatible polymeric material, or mixtures thereof, or A copolymer; polylactic acid, polyglycolic acid or a copolymer thereof; polyanhydride, polycaprolactone, polyhydroxybutyrate valerate. Still other biocompatible metals, alloys, or other biodegradable polymers or mixtures or copolymers may be used.

  Aortic stent graft 202 may include a biocompatible graft material attached to at least a portion of any stent. The graft material may be bonded to the prosthetic valve. In one embodiment, the graft material forms a lumen that is adapted to seal the wall of the aorta at a location proximal to the aortic annulus. In this embodiment, blood flows through the lumen of the stent graft, and the prosthetic valve regulates unidirectional flow of blood through the prosthesis.

  The biocompatible graft material is preferably nonporous so that it does not leak upon application of physiological forces. The graft material is preferably formed from woven DACRON® polyester (VASCUTEK®, Renfrewshire, Scotland, UK). Preferably, the graft material is formed seamlessly. The tubular graft is formed from any other material that is at least substantially biocompatible, including other polyester fabrics, fabrics such as polytetrafluoroethylene (PTFE), expanded PTFE, and other synthetic materials. May be. Also highly preferred are natural biomaterials such as collagen, especially produced collagen materials known as extracellular matrix (ECM), such as small intestine submucosa (SIS). Elastic elements may be incorporated as a property of the fabric or by a post treatment such as crimping. The size of the graft may vary according to the size of the artery to be treated. For each patient, a graft may be selected that has a diameter that exceeds the diameter of the transplant patient's artery. The stent is expected to be subjected to a sufficient radial outward force to seal between the graft material and the inner wall of the aorta.

  To secure the aortic stent graft to the wall of the arterial lumen, the balloon expandable stent 204 and / or the self-expandable stent 208 preferably includes an attachment system. A preferred attachment system includes an arterial wall engaging member, eg, a process or barb 230 as shown in FIGS. 2-4, 8-11 and 16.

  Preferably, the sharp metal barbs 230 protrude outward from the surface of the prosthesis 202. The barbs 230 may be attached to one or more members of the prosthesis 202. In one embodiment, barbs 230 are attached to self-expanding stent 208. In other embodiments, barbs 230 are attached to balloon expandable stent 204. In still other embodiments, barbs 230 are attached to both self-expanding stent 208 and balloon expandable stent 204. The barbs 230 face in the caudal direction, the cranial direction, or both directions. The barbs 230 may be soldered, brazed or welded to the stent and may be integrally formed at any point, for example by etching. The number of barbs is variable. In one embodiment, barbs 230 extend from self-expanding stent 208 and may engage the wall of the ascending aorta when deployed, with additional barbs extending from balloon expandable stent 204 and coronary veins. The sinus may be engaged. The aortic stent graft may be used with or without barbs. If the barbs are omitted, such that the radial force acting on the coronary sinus and ascending aorta is sufficient to hold the balloon expandable stent 204 and the self-expandable stent 208 in place, respectively. A stent may be formed.

  With reference to FIGS. 8 and 9, the arrows indicate the outward bending of a typical barb 230. Point A shows the apex of the barbs 230 and points B and C show the attachment points of the barbs 230 to the stent. If the stent expands during deployment, ΔAC (AC difference) should exceed ΔAB (AB difference) if the barbs 230 remain in the plane of the stent. However, the stent material cannot elongate or adapt greatly. This difference is solved by the movement of the apex A of the barbs 230 outward and downward, as indicated by the arrows in FIGS.

  In the absence of a balloon, the barbs 230 may move into the lumen of the stent. To ensure that the barbs 230 move as planned, the barbs 230 may be formed such that the starting point is slightly bent outward as shown in FIGS. 8-11. Sharp cusps can be formed to function as barbs, especially in very short stents. In this embodiment, the initial bend is even more important. Otherwise, the sharp tip will puncture the balloon. In a preferred embodiment, as illustrated in FIG. 11, the stent has barbs 230 facing outward from each apex in the expanded state.

  As described above, the aortic stent graft 202 preferably includes a prosthetic valve 210. The purpose of the prosthetic valve 210 is to replace the inherently damaged or reduced ability of the aortic valve function in the transplant patient. The prosthetic valve 210 is preferably placed at the distal end of the conduit 206 further away from the heart. In one embodiment, prosthetic valve 210 is coupled to conduit 206 by stitching.

  Prosthetic valve 210 preferably includes one or more leaflets. The tubular conduit longitudinally sutured to the opposite side of the neck of the self-expanding stent 208 functions exactly as a bicuspid valve. In other embodiments, three suture lines produce a tricuspid valve with less redundancy. Preferably, as shown in FIGS. 2-4, the prosthetic valve 210 includes three leaflets. The leaflets are placed in the prosthesis so that the leaflets mimic the native aortic valve. When the pressure on the proximal side of the prosthetic valve 210 exceeds the pressure on the distal side of the prosthetic valve, the prosthetic valve 210 “opens” and blood flows. In this way, the artificial valve 210 regulates the flow of fluid in one direction from the heart to the aorta.

  The leaflets of the prosthetic valve 210 are at least substantially biological, including, for example, polyester fabric, polytetrafluoroethylene (PTFE), expanded PTFE, and other synthetic materials known to those skilled in the art. It may be made from a compatible material. Preferably, the leaflets are manufactured from natural biomaterials. The leaflets may include generated collagen material, such as an extracellular matrix. The extracellular matrix may be small intestine submucosa, gastric submucosa, pericardium, liver basement membrane, bladder submucosa, tissue mucosa, dura mater and the like.

  A normal native aortic valve is hung from above via a fitting to the wall of the tubular sinus between the coronary ostium and has a complete sized and shaped leaflet to fill the space in the annulus. Have. Although the hung valve resists the force acting on the closed leaflets caused by diastolic blood pressure via the attachment to the downstream support, the struts of modern stents just woven the fabric. It is also possible to support the membrane “valve” of the prosthetic valve from below so as to support it. This method is described below and is particularly advantageous where the valve base is wide and there are few suitable locations for downstream anchoring.

  Various artificial valve structures may be used. These structures preferably have at least two membranes that overlap the hole / gap / lid so that there is no direct path from one side to the other. During the flow phase (aortic valve systole, mitral valve diastole), the membrane lifts from the underlying support and leaves, allowing blood to escape through these holes. This works best if the outer membrane is slightly slacker than the inner membrane. A wide variety of gaps and lids can be used.

  In the embodiment shown in FIG. 12, the inner membrane has a central hole 250 and the outer membrane has a series of peripheral gaps 260 that can be liquid passageways. In some embodiments, the gap 260 may be formed in substantially the entire area of the outer portion so that the intervening fabric is only a series of radial ropes. FIG. 12 illustrates the operation of such a prosthetic valve during A) diastole and B) systole. The arrows in FIG. 12B indicate the direction of blood flow through the gap and thus through the valve during systole.

  The prosthetic valve lid need not be a soft membrane. The valve lid may be somewhat rigid to support itself in the presence of a primitive peripheral attachment mechanism. A single disk may be formed in situ from a spiral strap, such as a flattened watch spring. If the entire valve is conical, the longitudinal force created by the diastolic pressure gradient is transmitted to the edge, where the rigid stent anchors the mechanism to the annulus. By separating the coil layers, a flow occurs during the systole.

  In some embodiments, the anchoring / support framework for the prosthetic valve 210 can be, for example, cylindrical, flat spherical, donut shaped, double disc shaped, etc., as illustrated in part in FIGS. Can take many shapes. In all of these, the donut shape provides greater support by tensioning the valve membrane rather than contacting the underside of the membrane directly. FIG. 13 shows one embodiment of a reticulated sphere or donut shape, illustrating the location of the outer membrane 270, the inner membrane 272, and the radial gaps 274.

  As shown in FIG. 14, the double disc shape is formed with a substantially completely impervious (no gap or hole) coating to function as a barrier or barrier rather than as a valve. obtain. In practice, one side of the valve may be thinner than the other side to close the space in the blood vessel. The thin side is placed outside the space and exhibits a smooth and flat surface. The thicker side is placed inside the space and closes the space, while providing stability.

  FIG. 14 illustrates the position of the valve membrane 280 and the original aortic valve 282. The direction of blood flow is indicated by arrow 284. The structure of the valve, which is a reticulated sphere, benefits from the beginning and end of the metal wire of the fabric at the edge of the disk, for example, as shown in FIG. These tend to pierce the surrounding tissue (or intervening tissue in the case of a double disc shape) and stitch the net in place.

  In general, the support frame need not be only a reticulated sphere or disk. In some embodiments, as shown in FIG. 15, the membrane may be conical (tent-like), for example, similar to a Greenfield® filter spanning a metal wire. In FIG. 15, a valve membrane 292, an umbrella frame 294, and one or more mounting rods 296 are illustrated.

  The aortic stent graft is introduced, delivered, and deployed into the vascular system of the implanted patient using an indwelling device or introducer. The indwelling device delivers and deploys the aortic stent graft in a position to replace the aortic valve inside the aorta, as shown in FIGS. The indwelling device may be shaped and dimensioned for incision in the abdomen for delivery and placement in the lumen. Typically, indwelling devices include cannulas or catheters and can have a variety of shapes. The aortic stent graft may be folded radially and inserted into the catheter or cannula using conventional methods. In addition to the cannula or catheter, it may be necessary to provide various other elements in order to obtain the most suitable delivery and placement system for the intended purpose. These include, but are not limited to, various external sheaths, pushers, stoppers, guide wires, sensors, and the like.

  Examples of delivery systems for intraluminal devices are known in the art. United States Patent Application Publication No. 2003/0149467, “Methods, Systems, and Devices for Delivery of Stents” provides examples of available stent delivery systems. Another example of a system and method for delivery of an endoluminal device has already been described in US Pat. No. 6,695,875 “Intraluminal Stent Graft”. WO 98/53761 “Prosthesis and prosthesis placement method” discloses a prosthesis introducer that holds the prosthesis so that both ends can be moved independently. Similarly, Zenith® TAA endovascular graft uses a delivery device commercially available from Cook Company, Bloomington, Indiana.

  In one embodiment, a trigger wire release mechanism is provided to release the retained end of the stent graft. The trigger wire release mechanism includes a stent graft retention device, a trigger wire that couples the stent graft to the stent graft retention device, and a control member for separating the trigger wire from the stent graft retention device. Preferably, the trigger wire device includes at least one trigger wire extending from the release mechanism via the indwelling device. The trigger wire is engaged to the proximal end of the aortic stent graft. In a preferred embodiment, the aortic stent graft is modular and includes multiple portions, but there are multiple trigger wires extending from the release mechanism through the indwelling device, each of the trigger wires engaging at least a portion of the aortic stent graft. May be. Preferably, the aortic stent graft comprises three members (balloon expandable stent, conduit, self-expanding stent). Thus, in a preferred embodiment, three trigger wires individually engage each of the three members of these prostheses. By individually controlling the placement of each of the members of the prosthesis, overall control of the placement of the prosthesis is possible.

  FIG. 16 shows a typical introducer used to deploy the aortic stent graft described above. The introducer is used to place the aortic stent graft 202 into the patient's arterial lumen during a medical procedure. The introducer includes an external operating portion 301 and a proximal positioning mechanism or attachment region 302. The introducer also has a distal positioning mechanism or attachment region 303. During a medical procedure for deploying the aortic stent graft, the proximal attachment region 302 and the distal attachment region 303 are moved through the arterial lumen to the desired placement location. The external operating unit 301 is activated by a user operating this introducer, but is kept outside the patient's body throughout the procedure.

  As illustrated in FIG. 16, the aortic stent graft 202 is held in a compressed state by the sheath 330. Sheath 330 radially compresses aortic stent graft 202 beyond the distal portion of thin walled tube 315. Thin tube 315 is generally flexible and may include metal. The tube 341 may be formed of a resin, but is coaxial with the thin tube 315 and is on the radially outer side of the thin tube 315. The distal end of tube 341 is adjacent to the proximal end of aortic stent graft 202. Tube 341 acts as a pusher to release stent graft 202 from the introducer during delivery.

  The tube 341 is “thick”. That is, the wall thickness of the tube 341 is several times the wall thickness of the thin tube 315. Preferably, the tube 341 is five times thicker than the thin tube 315. The sheath 330 is coaxial with the thick tube 341 and is located on the radially outer side of the thick tube 341. As shown in FIG. 16, the thick tube 341 and the sheath 330 extend proximally to the external operation unit 301. Thin wall tube 315 extends to the proximal end of the introducer. The introducer further includes hemostatic seal means 331 disposed radially around the sheath and thick tube 341. The hemostatic seal means 331 controls blood loss through the introducer during the procedure.

  The introducer may include an aortic stent graft control member 381 as illustrated in FIG. The stent graft control member 381 is disposed on the dilator portion 334 of the external operation unit 301. During deployment of the aortic stent graft 202, the sheath 330 is withdrawn proximally over the thick tube 341. The hemostatic seal means 331 generally fits securely around the sheath 330 and creates significant friction between the sheath 330 and the thick tube 341. As a result, it is difficult to pull out the sheath 330 beyond the thick tube 341. In order to overcome this friction, the operator must grip the thick tube 341 very tightly. Due to the difficulty in grasping the thick tube 341, the axial position of the aortic stent graft 202 may be impaired. The control member 381 makes this problem easier by allowing the operator to better grasp the dilator and reducing the force that the operator must apply to control and stabilize the thick tube 341 during withdrawal of the sheath 330. Solve. The control member 381 is generally tubular and includes an inner dilator facing surface 382 and an outer gripping surface 383. The control member 381 is on the thick tube 341 between the hemostatic seal means 331 and the release wire actuating portion to allow the operator to use the control member 381 at any position along the dilator. It is arranged to be slidable.

  The outer gripping surface 383 is designed so that the control member 381 fits comfortably and securely in the operator's hand. In this way, the outer gripping surface 383 may have a diameter that greatly exceeds the diameter of the thick tube 341. The outer gripping surface 383 may be generally axially uniform. In other embodiments, the outer gripping surface 383 may be generally non-uniform in the axial direction, resulting in a curved gripping surface. FIG. 16 illustrates a control member 381 having a generally non-uniform outer gripping surface 383. In FIG. 16, the control member 381 is generally shaped like an hourglass. The outer gripping surface 383 may include a smooth surface finish, or alternatively, the outer gripping surface may include a rough or rough surface finish. A rough or rough surface finish is beneficial. This is because the contact surface area between the operator and the control member 381 is increased, thereby increasing the influence of the operator. A number of surface finishes may be selected to provide various practical and tactile benefits.

  The control member 381 is generally deformable such that the control member 381 compresses the thick tube 341 when the operator grips the control member 381. The control member 381 transmits the force applied by the operator to the thick wall pipe 341. The dilator facing surface 382 may include a generally smooth surface. Alternatively, the dilator facing surface 382 may have a rough or rough surface. The rough or rough surface creates a more “sticky” or “sticky” contact between the control member 381 and the thick tube 341, thereby increasing the force transmitted to the dilator by the operator. Also good.

  The dilator facing surface 382 may include a generally uniform surface. Alternatively, the dilator facing surface 382 may include a generally non-uniform surface. For example, the dilator gripping surface 382 may include a plurality of engageable protrusions that extend radially inward toward the thick tube 341. When the operator grips the control member 381 with respect to the thick tube 341, the engageable protrusion engages with the surface of the thick tube. The engageable protrusions increase the contact surface area between the control member 381 and the thick tube, thereby increasing the force that the control member transmits to the thick tube 341 from the operator. The engageable protrusions may include any geometric or non-geometric shape. For example, the engageable protrusions may include an “O” shape, a line shape, a dotted line shape, a “V” shape, and the like.

  The distal attachment region 303 includes a retention device 310. The retention device 310 retains the distal end of the aortic stent graft in a compressed state. The retaining member 310 includes a long tapered flexible extension 311 at its distal end. The flexible extension 311 includes an internal longitudinal hole that facilitates advancement of the tapered flexible extension 311 along the pre-inserted guidewire. The longitudinal hole also provides a passage for the introduction of a therapeutic agent. For example, it may be desirable to supply a contrast agent for performing angiography during the placement and placement of a medical procedure.

  The distal end of thin tube 315 is coupled to flexible extension 311. The thin tube 315 is flexible so that the introducer can be easily advanced. The thin-walled tube extends to the operation unit 301 via the introducer on the proximal side and terminates at the connecting means 316. Thin tube 315 is in mechanical communication with the flexible extension and allows the operator to manipulate the distal attachment region 303 in the axial and rotational directions with respect to the aortic stent graft 202. The coupling means 316 is applied to accept the syringe and facilitate introduction of the reagent into the thin tube 315. Thin tube 315 is in fluid communication with flexible extension 311 and flexible extension 311 introduces the reagent into the arterial lumen via the hole.

  The trigger wire release operation part of the external operation part 301 includes an elongated body 336. Distal trigger wire release mechanism 324 and proximal trigger wire release mechanism 325 are disposed on elongate body 336. End caps 338 are disposed at the proximal and distal ends of elongated body 336. End cap 338 includes longitudinally facing parallel facing surfaces that define a distal plug 388 and a proximal plug 389. Distal trigger wire release mechanism 324 and proximal trigger wire release mechanism 325 are slidably disposed on elongate body 336 between distal plug 388 and proximal plug 389. Distal plug 388 and proximal plug 389 hold distal trigger wire release mechanism 324 and proximal trigger wire release mechanism 325 on elongate body 336. The actuating portion includes a locking mechanism for limiting axial displacement of the trigger wire release mechanisms 324, 325 on the elongated body 336.

  Referring to the external operation unit 301, the pin vise 339 is attached to the proximal end of the elongated body 336. The pin vise 339 has a screw cap 346. When screwed, the vise jaw tightens (engages) the thin metal tube 315. The thin tube 315 can only move with the elongated body 336 when the vise jaw is engaged. Therefore, the thin tube 315 can move only with the thick tube 341. Closing the screw cap 346 allows the entire assembly to move as a unit with respect to the sheath 330.

  Self-expanding stent 208 causes aortic stent graft 202 to expand during release from introducer 301, as shown in FIG. The stent graft shown in this example also includes a barb 230 extending from the distal end of the self-expanding stent 208. When the self-expanding stent 208 is deployed (released), the barbs 230 secure the distal end of the aortic stent graft 202 to the surrounding lumen (not shown). Upon placement in the lumen, the balloon expandable stent 204 expands and expands. The expansion of the balloon expandable stent may be caused by inflation of the catheter between the sleeves so that both ends of the stent are withdrawn from the respective sleeves and the stent is released and expanded into place. Tubular conduit 206 is also expanded upon release from the introducer. When the tubular conduit 206 is positioned between the balloon expandable stent 204 and the self-expanding stent 208 and contacts the two stents, the expansion of the two stents 204, 208 results in the expansion of the tubular conduit 206 as well. . Preferably, the tubular conduit 206 is thin-walled, which aids expansion when released.

  While various embodiments of the invention have been described, the invention should not be limited in any other way in view of the appended claims and their equivalents. Further, the advantages described herein are not necessarily the only advantages of the present invention, and it is not necessarily expected that each embodiment of the invention will achieve all of the described advantages.

  The features of the different embodiments described in this document may be combined with each other in any suitable manner, so that the features described in connection with one embodiment relate only to that embodiment. It should be understood that the invention is not limited to being used.

  The prosthetic valve 210 typically does not physically replace the heart valve, leaving the heart valve untouched surgically, and the prosthetic valve 210 is added to the heart valve to perform the function of the heart valve. I want you to understand that again. However, it is not excluded that the artificial valve 210 physically replaces the heart valve.

It is not excluded that more than one valve is provided in the prosthesis.
This patent application claims priority benefit of US Provisional Application No. 60/986908, filed Nov. 9, 2007 and entitled “Aortic Valve Stent Graft”, the disclosure of which is in its entirety. Incorporated by reference.

Claims (7)

An endoluminal prosthesis,
A first stent;
A tubular conduit provided with an aortic valve replacement, wherein at least a portion of the tubular conduit overlaps at least a portion of the first stent, and the aortic valve replacement extends beyond the first stent; further,
A second stent extending beyond the tubular conduit, operable to overlap at least a portion of the tubular conduit;
The first stent, the tubular conduit, and the second stent are arranged coaxially to pass fluid in one direction through the prosthesis;
The first stent comprises a balloon expandable stent and the second stent comprises a self-expanding stent;
An endoluminal prosthesis with no overlap between the first stent and the second stent.   The endoluminal prosthesis of claim 1, wherein the self-expanding stent at least partially surrounds the tubular conduit, and the tubular conduit at least partially surrounds the balloon expandable stent.   The endoluminal prosthesis of claim 1, wherein both the balloon expandable stent and the self-expanding stent at least partially surround the tubular conduit.   The endoluminal prosthesis according to any one of claims 1 to 3, wherein the aortic valve replacement includes an artificial valve.   The endoluminal prosthesis according to any of claims 1 to 4, wherein the aortic valve replacement is placed at the distal end of the tubular conduit.   The endoluminal prosthesis according to any one of claims 1 to 5, comprising one or more barbs.   The endoluminal prosthesis according to any one of claims 1 to 6, wherein at least one of the first stent and the second stent includes a braided bottle stent.

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